lumbocostoabdominal triangle

[lŭm′bō-kŏs′tō-ăb-dŏmə-nəl]
n.
  1. An irregular area bounded by the inferior posterior serratus muscle, the abdominal internal and external oblique muscles, and the erector muscle of the spine.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.